This invention relates to a hydraulic brake system for vehicles, and more particularly to a hydraulic brake apparatus with automatic braking means which is actuated to apply brakes according to an electric signal irrespective of a foot brake pedal operation.
There has been proposed an automatic brake system which comprises a radar device for detecting an obstacle in the course of the vehicle and generating an output signal, a computer for generating an electrical warning signal in accordance with the output signal, and electric motor means including solenoid coil assembly to be actuated by the electric warning signal thereby applying brakes. Such automatic brake system is very useful in safety of the vehicle because the brake may be applied not only by the foot pedal depression but also by the electrical automatic means even if the vehicle driver should be unaware of the obstacle on the road.
In one of the conventional automatic brake systems the foot brake pedal of vehicle is adapted to operate according to energization of the electric motor means. This system is undesirable since a large size of electric motor means is required thereby resulting in high cost. In another conventional brake system there is provided a hydraulic actuator which is actuated by energization of the electric motor means thereby depressing the foot brake pedal. This system is also undesirable because of requirement of the hydraulic actuator which requires additional space and pipes of the vehicle brake system.